All "H" pipe VS "X" pipe questions

[Phil Nelson]

All of the cars shows I watch anymore show them putting on exhaust systems with an X-pipe. Is the X-pipe that much better than the H-pipe?

Has anyone had a H-pipe and changed nothing else, but went to an X-pipe?

I am running 2 1/4" exhaust with Flowmasters, would changing to an X-pipe help reduce the resonate noise coming up through the floor? (my exhaust runs all the way out to the rear bumper)

[bigc]

if you do a search on this in the forums you will find that x pipes tend to give more of a performance boost than an H pipe. I don't remember the difference being huge but go X if you don't have H already.

[72Orange]

Someone did some research on "X-Pipe" vs "H-Pipe" vs no crossover and tested the results with different size pipes and mufflers etc. I think it was a Pontiac related project but should apply to anything. I think the difference was significant between "X" and "H" pipes.

[72Orange]

Finally found it

http://www.pontiacstreetperformance.com/psp/exhaust3.html

[NovatoriusRex]

Someone did some research on "X-Pipe" vs "H-Pipe" vs no crossover and tested the results with different size pipes and mufflers etc. I think it was a Pontiac related project but should apply to anything. I think the difference was significant between "X" and "H" pipes.

Here's the article 72 is referring to. Reading this is what caused me to put an X-pipe system on my car vs. an H-pipe system. It looks like it's worth about 1/10th in the quarter on this guys test.

http://www.pontiacstreetperformance.com/psp/exhaust.html

[Paul Wright]

I ran an H pipe on my Nova back in the seventies. It improved torque but really changed the tone of the exhaust. The X pipe configuration has replaced the H pipe design. If you want that true dual exhaust sound then don't put either on.

[NovatoriusRex]

I ran an H pipe on my Nova back in the seventies. It improved torque but really changed the tone of the exhaust. The X pipe configuration has replaced the H pipe design. If you want that true dual exhaust sound then don't put either on.

One thing I've noticed, and also heard from discussions around here and other sites on the net, is that my X-pipe system has a different sound from most of the other cars I hear at the shows. It's very smooth at the tailpipe and not horribly loud. This could be due to my muffler choice also, but it doesn't have the classic dual exhaust note to it. It's perfect for what I wanted hear out of my car. :) At speed it's kinda fun too. :D

[David_D.]

A tech article in one of the recent National Dragsters stated that stockers and super stockers are starting to use X pipes more due to torque gains over headers and torque tubes.

[whitelightning]

One thing I've noticed, and also heard from discussions around here and other sites on the net, is that my X-pipe system has a different sound from most of the other cars I hear at the shows. It's very smooth at the tailpipe and not horribly loud. This could be due to my muffler choice also, but it doesn't have the classic dual exhaust note to it. It's perfect for what I wanted hear out of my car. :) At speed it's kinda fun too. :D


I agree totally with the above. I put an X on my dual exhaust, the idle mellowed out big time, at cruising speed the sound also lowered dramatically, also felt a minor, yet positive, improvement in seat of the pants feel. Couldn't believe the difference made with all things being equal, with the exception of the added X pipe.

The theory behind it is, the X pipe tricks the system into thinking its larger than it is, hence improved flow and performance.

If someone is looking for more internet info to back up these claims, here is one I found using a brand F car. :)


http://carcraft.com/techarticles/69238/

[tpinovaII]

I was just wandering if anyone had seen this X-pipe design before. These guys seem to have come up with a slick way to build their own in-house. I found it interesting.

http://www.customexhaustsystems.com/

[the FLYER]

i'm thinkin' it's kinda what Dale (teddisnoke) was talkin' 'bout a while back... looks like a nice set up...

[tpinovaII]

If I were in Texas, I would probably have to pay these guys a visit about doing some work. I like their way of thinking.

[Pro-touring72]

to me just looks like an x pipe with dumps.
http://www.customexhaustsystems.com/xpipe2.jpg

[4door64]

Yeah ive herd good things about them from some guys here in town, I plan on taking my car up there for a exhaust system when I get the 454 put in:cool:

[Mike Goble]

I wonder how the wave physics compares to a tangentially siamesed x-pipe.

[69NovaSS]

I know this get asked all the time. BUT other then the obvious visual differences between the two types of balance tubes what is the difference? Does one of them work better for a street car while the other works better on a drag car/race car? Is one better for torque? Why would you choose one style over the other? Also how do they both effect the sound of the car?

Thanks in advance:)

[ChevyII MD]

So is that a little chamber that the pipes are going into and out of?
Would that hinder/help thae flow?

Mark

[Nova72]

I've had both on my BB. For me it came down to sound. The X pipe had a higher pitched Indy car sound and the H pipe had a lower muscular rumble to it, which I personally like better, so I chose the H pipe. I've read that the X pipe is suppose to be a little better in overall performance gain. Personal preference I guess :) .

[Mike Goble]

Jim Hand did some tests a while ago:

http://www.boyleworks.com/ta400/psp/exhaust.html

[69NovaSS]

Jim Hand did some tests a while ago:

http://www.boyleworks.com/ta400/psp/exhaust.html

Thats very interesting reading Mike...I guess the "X" pipe is the way to go but the link itself says that either crossover style is useful its just that the "X" style gave addition improvements over the "H" style. For those that dont want to read the link here is the general findings from the link


1. Always use a crossover of one kind or another. Our tests indicate that the X type gives additional improvements over the H type.

2. Mount the mufflers as far to the rear of the chassis as possible. An important characteristic of the exhaust system (behind the headers) is its ability to dissipate heat energy. Heat loss brings with it, gas volume reduction, enabling smaller mufflers and pipes to be used without penalty.

3. Always us the largest case muffler that you can fit under the chassis possible. The larger internal volume allows additional acoustical energy to be absorbed ,dissipated and eliminated.

4. Unless an engine is in the 500+ horsepower level or run at very high RPM, the maximum tailpipe size required for minimal power loss is probably 2.5" diameter. When the exhaust pipes and mufflers drop the temperature significantly, the volume of the exhaust gas is reduced and tailpipe sizes is not as critical.

5. When you must adapt various pipe sizes, always use long tapered cone reducers, such as, those available from Flowmaster. You can also use a crossover that has reduced pipe sizes built into it.


Now its interesting that their findings for a muffler is very simular to the findings poster by other member in another thread:

Dawg Im in Marion, about halfway between Hickory and Asheville.
Flowmaster 40 series 2 chamber flows 60% of what an open 2.5" pipe will flow.
Dynomax Ultra-flo flows 93%
Dynomax welded Ultra-flo flows 100%
Magnaflows are 83% for the 14" long and 85% for the 18" long.
I dont have any info on the Flomaster super 40 series.
Sound levels at 3500 rpm(with a big cubic inch engine) in same order as above:
98dB
91dB
93dB
94,95dB
A crossover pipe(x-pipe) will usually lower the sound level a little depending on rpm range.
All tests were done using a large displacement(454+cubic inch) engine.
Goerlichs Xlerators flow nicely too at 94 and 97% ;)
So I guess Flowmaster isnt the master after all.
Just as a refference a popular brand OEM mufler flows 53%
Stay away from the Magnaflow baffled mufflers though they dont flow as well......but still flow better than the Flowmasters.

Good to know info:)

[FunkyNova66]

I have an x-pipe with 3" exhaust and it sounds awesome.:beer:

[Mike Goble]

Dr. Gas has a gallery of sound bytes of x-pipe cars:

http://www.drgas.com/photogal/thumbnails.php?album=14

[joey d]

The way I read the article, a 3" x pipe going into my 2 1/4 stainless exhaust is the way to go(i don't want to buy another $600 exhaust just to upgrade to 3" all the way) am I right ???

[Fast Eddie]

Used 3" pipe with X pipe and Flowmaster 50. Pipes come out pointing down, behind the rear tire. See website:)

[hotrodgary]

I'm runnin BB w/ 2" primary's & a 3" full exhaust with an x-pipe, and Dynatech mufflers, made it all myself, its LOUD, but sounds friggin awesome!!!! I like the raspy "circletrack" sound when you crack open the throttle!!!

Later,
Gary

[new2novas]

doesn't look special to me...has the dumps for cutouts and the x pipe section seems to be a peice of oval tubing more like a chamber of large area rather than an x pipe

[bowtie0069]

Darryl Bassani claims his X-pipe makes more power than a conventional one, it has a plenum chamber at the crossover. He's been trying to get me to try his deal for a few years. Maybe one of these days....
He has some killer equipment--mandrel bends up to like 5" or more for the deisel crowd. Makes mufflers any size you want.

[Necro]

nothing spectacular. the bends are not mandrel , they are lesser quality muffler bends,(wrinkles in the bend). the swedge at the flange for the headeris not smooth. its a nice street car exhaust. thats all.

when i had my custum exhaust biz. i made the same stuff . without the x pipe , back then we only made h-pipes. used mandrel bends and curved swedges.

[tpinovaII]

to me just looks like an x pipe with dumps.

You looked at the entire website and saw one picture? I hate the ideas of dumps on any car. Talk about a flow restriction. What I saw was an x-pipe idea that could be easily replicated by anyone with basic fabrication skills. It is not state of the art. It is by no means the ultimate exhaust. It is just another option for someone who is thinking of going to Midas (garbage work). I thought someone might take some good ideas away from this. My bad.

http://www.customexhaustsystems.com/65%20Mustang%20S3.JPG

[Nova SS]

I would worry that the dump pipes would act as resonating chambers, and cause all kinds of strange effects on flow.

[1965proSTREET]

well this may be a bit off the subject ( the title WAS unusual x-pipe) but does anyone have pics of an x pipe off of fenderwell headers? has anyone done it... i am not very exhaust savvy so pardon my limited knowledge...

[Mike Goble]

Mike Harris made an x-pipe under his car with fenderwell headers a few years ago.

[Nova SS]

http://img.photobucket.com/albums/v630/Novass301/Mikepictures149.jpg

[SuperNova69]

http://img.photobucket.com/albums/v630/Novass301/Mikepictures149.jpg

That looks like it's just a couple of pipes in the shape of an X that got welded together at the middle...doesn't even look like it'll do anything...

:confused:

Matt

[Mike Goble]

That looks like it's just a couple of pipes in the shape of an X that got welded together at the middle...doesn't even look like it'll do anything...

:confused:

Matt

What did you expect? How would you compare it to the original x-pipes?

[Nova SS]

That looks like it's just a couple of pipes in the shape of an X that got welded together at the middle...doesn't even look like it'll do anything...

:confused:

Matt

Yep thats what it is.

Its hard to tell becasue of the shadowing but the fistula's area equals the pipes diameter, I did not know much about exhaust work until Mike Goble sent me some links so I decided to give it ( a x pipe) a try.

With this exhaust ( running out under the rear bumper) and running a mild 427 it has turned a 10.23 so I consider it a "succes story". Oh ya it sounds wicked as hell at 7000 RPM !

[SuperNova69]

What did you expect? How would you compare it to the original x-pipes?

Well what would that even do? What I originally meant was, it looks like they took two seperate pipes, bent them to touch and welded them together. Like they aren't even open to each other, you know? I just don't see what that would do at all if they actually ARE like that.

:confused:

Matt

[Mike Goble]

See what an education you get here? I'll bet you don't use the word fistula around the water fountain much. This is what's known as a tangentially siamesed crossover, with a slice of each bend removed on a tangent before they are welded together. The ones you get from Dr. Gas have a brace welded between the halves.

[SuperNova69]

See what an education you get here? I'll bet you don't use the word fistula around the water fountain much. This is what's known as a tangentially siamesed crossover, with a slice of each bend removed on a tangent before they are welded together. The ones you get from Dr. Gas have a brace welded between the halves.

Ah, interesting. So you're saying the Dr. Gas ones are like I was saying? That they don't have a fistula?

Interesting...

I checked around and I found a place that can give me a 3" exhaust system with X pipe and mufflers for pretty cheap...I might have to get that done, now...

BTW, thanks for educating me. :D

Matt

[Mike Goble]

Ah, interesting. So you're saying the Dr. Gas ones are like I was saying? That they don't have a fistula?


The ones you get from Dr. Gas have a brace welded between the halves.

So you're saying that I implied that you would think that because the Dr. Gas units units are braced that they don't have a fistula? How would they work? Osmosis? Tympanic coupling?

[Nova SS]

The system would be total ineffective if there was not an opening bewtween the two pipes. Just think of it as an extream "H" pipe without those nasty 90 degree turns for the exhaust pulse to fight with.

[Nova67ss]

That X pipe was a breese to manufactoring by myself, and for any other that can handle an hacksaw and a migwelder.

I took 2 60`elbow pipe and made a cut nearly as large as the pipe dia, then welded them together, this and 4 30`pipe´s and they are straight from collectors to mufflers..

Used the 2½" pipes

[SuperNova69]

The ones you get from Dr. Gas have a brace welded between the halves.

So you're saying that I implied that you would think that because the Dr. Gas units units are braced that they don't have a fistula? How would they work? Osmosis? Tympanic coupling?

That's my point, a lot of X pipes look like they don't have a fistula, so I thouht a lot of them were just pipes bent and welded by noob exhaust people that thouht they could make X pipes. I didn't mean to offend or anythin, it's just you said there was a brace between the halves. So it sounded like even if there was a hole, they welded a piece of metal between and that filled it up. :o

Matt

[ovrdrive]

Guys,

does anybody know the exact location you should put the "H" pipe on a dual exhaust system? In other words, how far from the headers should the "H" pipe be installed?

Tech info:

66 2-dr.
355 CID
200-4R
2.5' exhaust


Dan

[pete62conv]

I've heard of people painting or writing on the pipes with a crayon and seeing where it burns off at. Personally I think that sounds like the stupidest thing that I've ever heard. Put it where it's easiest and worry about somthing more important like '' am I out of beer?'' Kidding... cause I dunno. I'm not sure if you will ever get a strait answer or if it even matters. Amber Bock me.

[Mike Goble]

It depends on the operating range of the motor. I have a program by Larry Meaux of Meaux Racing Heads that figures things like that out.

[jade76]

I've heard in different places that they perform best directly after the headers, but I've also heard after the mufflers. I bought a universal x-pipe kit for my 76 from Summit. The kit came with the x-pipe and 4 short radius 45 degree elbows which are about 3-4 foot long. I had to cut about 4 inches off 2 elbows coming off the collector for proper alignment, connected the x-pipe and the other 2 extensions to the mufflers. I used Dual Flowmaster Delta 40 mufflers and tried my setup with the mufflers before the x-pipe and again with the x-pipe directly behind the headers and mufflers behind it. I personally had better results with the x-pipe directly after the headers.

As I've been told in plain terms, the principle is to evenly distribute your exhaust to the mufflers to prevent unequal exhaust pressure. My setup put the x-pipe approximately 2-1/2 ft. behind the collector. I can get an accurate measurement tomorrow if it'll help.

[ovrdrive]

Thanks for the reponses!!

I am going parts shopping tonight, (if the BOSS lets me, :D ) and see who has the better deal of the week, SUMMIT or JEGS. I guess from this post is that everyone is going with an "X" pipe vice the standard "H" pipe, correct?

MIKE, didn't you mention in another post about the differences between the H and X pipe?? For the price as it stands now, the H pipe is arround $30.00 and the X is $80.00. Is that $50.00 difference going to make that much of a deal on my exhaust??

Dan

[Ron Slabaugh]

Just swaped from a 2-1/4" H-pipe to a 2-1/2" X-pipe.

The H-pipe design left the collectors with about 5" of 2" pipe on each side, transitioned to 2-1/4", and the pipes came to within 5" of each other about 9" behind the u-joint. The H joined and the pipes continued along each side of the tunnel to the mufflers and out the rear bumper.

The X-pipe is the universal Summit kit. New 3" x 2-1/2" collectors were installed. The X is positioned where the H was the the routing is very similar.

Sound at the tailpipes is identical. I notice slightly more resonance inside the car with the X design.

Most significant is about 1-1/2" Hg manifold vacuum loss at part throttle in-town cruising with the X-pipe. I'll attempt to get some of that back in the next week or so tuning the carb with my LM-1.

[FunkyNova66]

Here is what an X-pipe sounds like. 3" mandrel bent, flo-pro v-force mufflers.

http://www.stevesnovasite.com/forums/showthread.php?t=43969&highlight=V-Force

[NovatoriusRex]

Here's what my 2.5" mandrel bent, x-pipe exhaust sounds like with Magnaflow mufflers. :D

http://www.67chevyii.com/updates/sounds/67ChevyII_burnout.mpg

[cmthomp2]

Whats the main difference between the two? im assuming flow? If i changed from an H pipe to the X pipe do u think it would change the sound of the car?

[Paul Wright]

Did u read Best of Tech All X pipe vs H pipe questions (http://www.stevesnovasite.com/forums/showthread.php?t=33539)?

[ovrdrive]

From the H to the X, you will notice a significant drop in your exhaust tone. I do have a video clip of my 66 but I am not able to post it yet. But, in the beginning, it had a dual 2 1/2 set-up with no H and super turbo mufflers. The second run has the X installed and "Cherry bomb" mufflers and there is a much deeper sound. I would definitely say "do it!", if you have the room.

Dan

[65chevy2see]

Hey funkynova, Your sound clip says that it no longer exists. I'd really like to hear it since I have the same headers as you.

[Seattle_Mike]

As Paul said, there's a whole section on it in the archives. The X pipe generally makes the exhaust note noticeably higher especially at higher rpm ranges. Some people refer to it as "it makes it sound like an Indy car", not quite but if you hear one, you will understand their comment. There are also some performance gains with the X pipe. I didn't have sufficient room, so did the next best thing...an H pipe.

[Dragnova67]

Ok,
My turn... :)

I need to meet a db requirement at our local track (PIR) and which one will generally have lower db's at the top end?????

[NovatoriusRex]

Ok,
My turn... :)

I need to meet a db requirement at our local track (PIR) and which one will generally have lower db's at the top end?????

Speaking of PIR, I was surprised that my 2.5" x-pipe system just barely meets their post-10pm noise limits at WOT. I think this is more due to my muffler choice than the exhaust system though x/h pipe detail though.

[cmthomp2]

I wanted to buy they X pipe section from pypes and replace that section on my cars exhaust. THis has the built in cut outs and it looks really clean

http://www.pypesexhaust.com/gallery29.html

[ERV JR]

I was considering taking to 3 1/2 45 deg bends cutting them open and tiging them together as an X pipe ,but was wondering if i would see a benifit of running an X pipe as opposed to running without one ? It would be hard to tuck the tubing ub there and the more bends will make it harder. I will be turning the motor to aprx 8500, its a 412 sbc with a decent size tune up in the plate ,, with 2 in primary to 3.5 collectors, should hopefully run high 8's